• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.2
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• pp.91-97
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• 2001

The effects of sudden changes of water temperature (WT) on the stress response and physiological change of the cultured olive flounder in large (FL) and small (FS) size, and fat cod (FC) were examined by manipulating WT (2 types) in a flow through seawater culture system with 6 tanks (water vol. 270 L/tank). The WT was decreased from $20^{\circ}C$ to $10^{\circ}C$ within 5 hours ($2^{\circ}C/hour$) and maintained at $10^{\circ}C$ for 21 hours (Exp. I), and it was raised from $20^{\circ}C$ to $30^{\circ}C$ within 5 hours and maintained at $30^{\circ}C$ for 21 hours (Exp.II). In Exp. I, the levels of blood hematocrit at 5 hours ($10^{\circ}C$) in FS was significantly decreased from $13.5\pm2.0\%\;to\;11.3\pm2.3\%$, but FC at 2.5 hours ($15^{\circ}C$) ($19.0\pm0.3\%\;to\;23.2\pm3.8\%$) was increased, The blood hemoglobin concentration of all fish in Exp, II was significantly increased until 8 hours after raising WT from $20^{\circ}C$ to $30^{\circ}C$. In Exp. I and II , the levels of plasma cortisol in FL, FS and FC was changed from $5.2\pm8.5ng/mL,\;4.4\pm4.5ng/mL\;and\;2.7\pm0.4ng/mL$, respectively, before sudden drop and rise of WT. The levels of plasma cortisol of in FL ($164.0\pm53.1ng/mL$) and FC ($207.9\pm25.4ng/mL$) were significantly increased by the lowering WT sharply during whole experiment. The FL ($12.6\pm2.0ng/mL$) and FS ($4.0\pm3.9ng/mL$) showed no significant differences in cortisol level according to sudden rise of WT (5 hours). But it in FC ($44.7\pm18.2ng/mL$) was increased. In Exp. I, the plasma glucose levels of all fish groups were decreased after 5 hours ($10^{\circ}C$), The plasma lactic acid concentration of FL and FS showed no significant differences until 5 hours after raising WT from $20^{\circ}C$ to $30^{\circ}C$, But it in FC was significantly increased with WT raise.

• Journal of Life Science
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• v.30 no.11
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• pp.931-938
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• 2020

Translationally controlled tumor protein (TCTP) is one of the most abundant proteins in various eukaryotic organisms. TCTPs play important roles in cell physiological processes in cancer, cell proliferation, gene regulation, and heat shock response. TCTP is also considered an important factor in the resistance to oxidative stress induced by dithiothreitol or hydrogen peroxide (H₂O₂). Arctic calanoid copepods have a variety of antioxidant defense systems to regulate the levels of potentially harmful reactive oxygen species generated by ultraviolet radiation in the Arctic marine ecosystem. However, information on the antioxidant activity of TCTP in the Arctic Calanus glacialis is still scarce. To understand the putative antioxidant function of the Arctic copepod C. glacialis TCTP (Cg-TCTP), its gene was cloned and sequenced. The Cg-TCTP comprised 522 bp and encoded a 174-amino acid putative protein with a calculated molecular weight of ~23 kDa. The recombinant Cg-TCTP (Cg-r TCTP) gene was overexpressed in Escherichia coli (BL21), and Cg-rTCTP-transformed cells were grown in the presence or absence of H₂O₂. Cg-rTCTP-transformed E. coli showed increased tolerance to high H₂O₂ concentrations. Therefore, TCTP may be an important antioxidant protein related to tolerance of the Arctic copepod C. glacialis to oxidative stress in the harsh environment of the Arctic Ocean.

• Journal of the Korean Institute of Landscape Architecture
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• v.44 no.2
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• pp.122-129
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• 2016

It is important to know the sensitivity of shrubs to de-icing salt in order to set guidelines for ecological tolerance of evergreen shrubs along roads. Therefore, the aim of this study was to investigate the influence of de-icing salt, calcium chloride($CaCl_2$), on the growth and physiological characteristics of three evergreen shrubs, Euonymus japonica, Rhododendron indicum, and Buxus koreana. Plants were exposed to calcium chloride at different concentrations(weight percentage, 0% as control, 1.0%, 3.0%, and 5.0%) through amended soil maintained from the start of the experiment in October of 2014 until termination in March of 2015. The survival rate, plant height, leaf length, leaf width, leaf shape index, number of leaves, fresh weight, dry weight, dry matter, root/top ratio, chlorophyll contents, fluorescence, photosynthesis, stomatal conduct, and transpiration rate were recorded. Elevated calcium chloride concentrations decreased plant height, leaf length, leaf width, leaf shape index, fresh weight, dry weight, dry matter, and R/T ratio of the three shrubs. Root growth responded more sensitively than the top growth to salinity. However Euonymus japonica was more tolerant to salt stress than Rhododendron indicum and Buxus koreana. Their growths were totally inhibited by $CaCl_2$ above 3.0% and 1.0% concentrations, respectively. Chlorophyll content, fluorescence, photosynthesis, stomatal conduct, and transpiration rate of both Rhododendron indicum and Buxus koreana were reduced sharply, while Euonymus japonica exhibited mild reductions compared to plants grown in control when increasing calcium chloride was used. Especially, the transpiration rates of Rhododendron indicum, and the photosynthesis and stomatal conduct of Buxus koreana were suppressed as the concentrations of calcium chloride increased. Therefore, Euonymus japonica should be considered as an ecologically tolerant species with proven tolerance to de-icing salt.

• Childhood Kidney Diseases
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• v.13 no.2
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• pp.215-221
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• 2009

Purpose : Thymus is a lymphoproliferative organ that changes size in various physiological states in addition to some pathological conditions. Thymus is susceptible to involution, and shows a dramatic response to severe stress. Thymic measurements may be helpful in various diseases. UTI (urinary tract infection) is most common bacterial infection in infants and VUR (vesicoureteral reflux) is a common abnormality associated with UTI. In our study, the size of thymus was compared on the premise that a greater stress is exerted on the body when UTI is accompanied by VUR, than when occurs on its own. Methods : Thymic size was measured on standard chest anteroposterior radiographs and expressed as the ratio between the transverse diameter of the cardiothymic image at the level of the carina and that of the thorax (CT/T). The medical records of 99 febrile urinary tract infection infants without other genitourinary anomalies except VUR were reviewed retrospectively. Results : Among 99 patients with febrile UTIs, 25 were febrile UTI without VUR and 74 with VUR. For the UTI with VUR group, there was a significant decrease in the thymic size compared to the those without VUR group ($0.382{\pm}0.048$ vs $0.439{\pm}0.079$, P<0.05). However, there were no differences in the duration of fever and WBC, CRP between the UTI with VUR and UTI without VUR. In addition, there were no differences in the cardiothymic/thoracic ratios between renal defects and renal scars in febrile UTI patients. Conclusion : The results of this study show that the shirinkage of thymus was more frequently found in the UTI patients with VUR. Therefore, awareness of the risks associated with thymic size is important for the appropriate work up and management of UTI patients.

• Journal of Aquaculture
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• v.19 no.2
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• pp.77-83
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• 2006

This study was conducted to investigate changes of hemolymph count, antioxidant enzyme activities (catalase: CAT and superoxide dismutase: SOD) and Heat Shock Protein 70 (HSP70) mRNA in hemolymph, hepatopancreas and gill of abalone (Haliotis sieboldii) exposed to various water temperatures. Abalones were exposed to 10, 15, 20, 25 or $30^{\circ}C$ for 0, 6, 12, 24 or 48 hours. Survival rate of abalone was 100% at 10, 15, 20 and $25^{\circ}C$, but 0% at $30^{\circ}C$. Hemolymph counts increased at lower water temperatures (10 and $15^{\circ}C$) and decreased at $30^{\circ}C$. SOD activity decreased immediately after exposure to lower or higher water temperatures compared to the control ($20^{\circ}C$) with an exception at $30^{\circ}C$ where the activity increased. At lower temperatures, SOD activity rose high after 24 hours, but decreased again at 48 hours. At $25^{\circ}C$, it decreased compared to the control. CAT activity decreased immediately after exposure to 10 or $25^{\circ}C$ compared to the control, and then was recovered to the initial level after increment. At $15^{\circ}C$, CAT activity was high after 6 hours, and then was recovered to the initial level after increment. At $30^{\circ}C$, the activity decreased throughout the experiment. The HSP70 mRNA expression in gill increased at lower temperatures compared to the control ($20^{\circ}C$) and $25^{\circ}C$. In this study, rapid change of wale, temperature caused stress response in abalone which had been raised at $20^{\circ}C$. At molecular level, HSP70 was expressed rapidly, but antioxidant enzymes like SOD and CAT were expressed later than HSP70. At 15 and $25^{\circ}C$ of water temperatures, the HSP70, SOD and CAT expression were stable with time. However, at $30^{\circ}C$, all abalone died possibly because they could not develop resistance to high temperature.

• Korean Journal of Agricultural and Forest Meteorology
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• v.24 no.3
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• pp.145-154
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• 2022

Due to abnormal weather conditions caused by climate change, natural disasters and damages are gradually increasing around the world. Global climate change as accompanied by warming is projected to exert adverse impact on production of potato, which is known as cool season crop. Even though, role of potato as a food security crop is expected to increase in the future, the climate change impacts on potato and adaption strategies are not sufficiently established. Therefore, this study was conducted to analyze the damage pattern of potatoes due to high temperature treatment and to evaluate the response of cultivars. T he high temperature treatment (35~38℃) induced heat stress by sealing the plastic house in midsummer (July), and the quantity and quality characteristics of potatoes were compared with the control group. T otal yield, marketable yield (>80 g) and the number of tubers per plants decreased when heat treatment was performed, and statistical significance was evident. In the heat treatment, 'Jayoung' cultivar suffered a high heat damage with an 84% reduction in yield of >80 g compared to the control group. However, in Jopung cultivar, the decrease was relatively small at 26%. Tuber physiological disturbances (Secondary growth, Tuber cracking, Malformation) tended to increase in the heat stress. Under heat conditions, the tubers were elongated overall, which means that the marketability of potatoes was lowered. T he tuber firmness and dry matter content tended to decrease significantly in the heat-treated group. T herefore, the yield and quality of tubers were damaged when growing potatoes in heat conditions. T he cultivar with high heat adaptability was 'Jopung'. T his result can be used as basic data for potato growers and breeding of heat-resistant cultivars.

• Current Research on Agriculture and Life Sciences
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• v.11
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• pp.43-54
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• 1993

This experiment was conducted at Andong county cropping season to investigate rice response and consequent changes in the physiological activities and agronomic characters of rice as affected by growth regulator treatments, and to determine how low temperature controls some plant growth mechanisms. Plant growth regulators, particularly ABA, applied to 15 DAT regardless of concentration, gave higher tar plant height and tiller number after 10days of low temperature treatment than did the untreated plant. However, the differences in plant height and tiller number among treatments diminished to plant growth. Chlorophyll content seemed to be enhanced by growth regulators under low temperature condition. The 10-day treatment of low temperature decreased chlorophyll content by more than 17% compared with the untreated control. The oxidizing activity of roots decreased sharply to 52.2a after 10 days in low temperature condition. On the other hand, ABA at concentration of $10^{-4}M$, highly attains oxiding activity of roots. Generally, plant growth regulators applied at 15 DAT under low temperature reduced grain yield more than did the untreated control which can be attributed to decreased yield components. When growth regulators were applied to booting stage, the tiller number did not show significant difference, whereas the significant difference in culm length at harvest was observed in all treatment as a result of different concentration of growth regulators. The growth regulators generally exhibited a significant effect on yield component except on panicle length. Grain yield of low temperature treated plot at booting stage was significantly influenced by application of growth regulators. This was due to decreased number of spikelet and low filled spikelet percentage. However, TIBA treatment at booting stage showed no significant differences in grain yield.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.58 no.2
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• pp.85-90
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• 2013

This study was conducted to examine the basis for the information to select the suitable potato varieties grown in new reclaimed land. The potatoes of five varieties were planted in the port with 4 different electrical conductivities of saturated extracts of soil taken the Saemangeum reclamation area, which was made of non-treatment salt and three concentrations of salt treatment, 1.6 dS $m^{-1}$, 3.2 dS $m^{-1}$, 4.8 dS $m^{-1}$, respectively. All of the potato varieties were uniformly emerged without missing plant in all treatment groups, even 4.8 dS $m^{-1}$ treatment group. According to the salt concentration of soil, required date to the emergence of the potato comparing to non-treatment salt was delayed 3-4 days in 1.6 dS $m^{-1}$, 6-10 days in 3.2 dS $m^{-1}$, 7-13 days in 4.8 dS $m^{-1}$, respectively, and the number of its branch decreased by 14-58% comparing to non-treatment salt depending on varieties. Since the increase of the salt concentration of the soil was more serious the decrease of the number of its branch, but plant height tended to increase when branch number per plant was small, which was depending on more number of its branch than salt concentration. Fresh tuber yield of potato comparing to non-treatment salt were decrease 33.7% in 1.6 dS $m^{-1}$, 59.5% in 3.2 dS $m^{-1}$, 79.3% 7-13 days in 4.8 dS $m^{-1}$, respectively. The threshold EC starting the growth inhibition of fresh weight decreased was 1.2 dS $m^{-1}$ for Chudong, 1.8 $m^{-1}$ for Chubeak, 1.9 $m^{-1}$ for Chugang and Chuyeong, and 2.0 $m^{-1}$ for Sumi, and EC which decreased 50% of dry weight index was 2.4 dS $m^{-1}$ for Chubaek, 2.45 dS $m^{-1}$ for Chudong, 2.81 dS $m^{-1}$ for Chugang, 3.03 dS $m^{-1}$ for Chuyeong, and 3.29 dS $m^{-1}$ for Sumi. The present results suggest that Sumi is considered to the suitable potato variety grown on saline soils.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.59 no.3
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• pp.293-298
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• 2014

This study conducted experiments on the reclaimed land of Saemangeum located in Jeongrabuk-do in order to gain basic information about growth characteristics and yield ability according to soil salinity. Having soil excluding salt as a control group, this study adjusted the specimens' soil salinity to level 4 and then planted four varieties including Ilmichal Corn to investigate the growth or grain yield according to salinity. About the corn establishment rate according to soil salinity, over 97% up to $3.2dS\;m^{-1}$ was established, and then, it was reduced gradually according to the increase of concentration. According to the salt concentration of soil more required growth duration from seeding to heading comparing to non-treatment salt was delayed, at $1.6dS\;m^{-1}$, two days were delayed, at $3.2dS\;m^{-1}$, four to six days were delayed differently by varieties, and at $4.8dS\;m^{-1}$, six to 10 days were delayed. About the plant fresh weight according to soil salinity, Chalok 4 and Eolrukchal indicated 93%~97% or so compared with the salt-free one at $1.6dS\;m^{-1}$, and Chalok No. 4 showed 79% at the salinity of $3.2dS\;m^{-1}$, too, and it was a relatively higher growth percentage than those of the other varieties. In terms of dried seed weight according to soil salinity, compared with the corns cultivated in the control group, averagely 12.1% was lowered at the time of cultivation at $1.6dS\;m^{-1}$, and $3.2dS\;m^{-1}$ 40% was lowered, and about 70% was lowered at $4.8dS\;m^{-1}$. According to the result of examining the point of time that dried seed start to reduce due to soil salinity with the regression equation, soil salinity which starts the reduction of grain weight is $1.67dS\;m^{-1}{\sim}2.18dS\;m^{-1}$, and it differs by varieties, and EC of 50% that the yield reduces in half is $2.96dS\;m^{-1}{\sim}4.45dS\;m^{-1}$. And the degree of influence on each of the growth factors according to soil salinity is founded to be in the order of establishment rate

• Korean Journal of Soil Science and Fertilizer
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• v.6 no.2
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• pp.115-127
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• 1973

Leaf discoloration of IR667 lines (tropical) and leading locals (temperate) in fields was classified according to the probable causes and nutritional disorder due to soil reduction in 1972 was investigated. 1. The causes of leaf discoloration in IR667 were low air temperature, soil reduction, seed born, insect bite, nitrogen depression, overdose pesticide, strong wind, early senescence and unknown one. 2. Leaf discoloration due to soil reduction which has been called Sageumbyeong by famers, was caused by the heavy application of $Ca(OH)_2$, compost and poor drainage followed by Zn and K deficiency and Fe toxicity. 3. About 30 days after transplanting deficiency concentration of K and Zn in leaf blade appears to be less than 2.0% and 20ppm respectively, and greater than 200ppm, 500ppm, and 1.0% respectively for toxicity or excess of Fe, Mn and Ca. and in the shoot 2.4% for K, 30ppm for Zn and 800ppm for Fe. The value of K/Ca should be greaterthan 2.0 for health. 4. When plants were damaged by soil reduction the contents of N, P, Ca, Mg, Fe, Mn, Na in shoot were increased and those of K, Zn, Si were decreased. 5. IR667 lines show in shoot higher content of N, P, Ca, Mg, Si, Na, and lower content K, Zn, Fe, Mn and lower root activity than local leading varietles in either healthy or disieased case, indicating IR667 lines are likely more suseptible to soil reduction damage. 6. Normal soil was less than 6.5 of pH and greater than -50 mv of Eh, but pH of problem soil was ranged from 6.7 to 7.4 and Eh from -100 to -190. 7. The root activity (${\alpha}$-naphthylamine oxidation) decreased at early stage of soil redudtion damage, then increased with severity and at the end it decreased again, but IR667 lines showed always lower root activity than local ones.